/*
* Copyright (c) 2006-2007 Erin Catto http:
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* Converted for The Render Engine v2.0
* Aug. 4, 2010 Brett Fattori
*/

Engine.include("/physics/common/b2Settings.js");
Engine.include("/physics/common/math/b2Math.js");

Engine.include("/physics/collision/b2Collision.js");
Engine.include("/physics/collision/b2Manifold.js");
Engine.include("/physics/collision/shapes/b2Shape.js");

Engine.include("/physics/dynamics/contacts/b2Contact.js");
Engine.include("/physics/dynamics/contacts/b2ContactNode.js");

Engine.initObject("b2PolyContact", "b2Contact", function() {

   var b2PolyContact = b2Contact.extend({
      
      // store temp manifold to reduce calls to new
      m0: null,
      m_manifold: null,
      
      constructor: function(s1, s2) {
         // The constructor for b2Contact
         // initialize instance variables for references
         this.m_node1 = new b2ContactNode();
         this.m_node2 = new b2ContactNode();
         //
         this.m_flags = 0;

         if (!s1 || !s2){
            this.m_shape1 = null;
            this.m_shape2 = null;
            return;
         }

         this.m_shape1 = s1;
         this.m_shape2 = s2;

         this.m_manifoldCount = 0;

         this.m_friction = Math.sqrt(this.m_shape1.m_friction * this.m_shape2.m_friction);
         this.m_restitution = b2Math.b2Max(this.m_shape1.m_restitution, this.m_shape2.m_restitution);

         this.m_prev = null;
         this.m_next = null;

         this.m_node1.contact = null;
         this.m_node1.prev = null;
         this.m_node1.next = null;
         this.m_node1.other = null;

         this.m_node2.contact = null;
         this.m_node2.prev = null;
         this.m_node2.next = null;
         this.m_node2.other = null;
         //

         // initialize instance variables for references
         this.m0 = new b2Manifold();
         this.m_manifold = [new b2Manifold()];
         //

         //super(shape1, shape2);
         //b2Settings.b2Assert(this.m_shape1.m_type == b2Shape.e_polyShape);
         //b2Settings.b2Assert(this.m_shape2.m_type == b2Shape.e_polyShape);
         this.m_manifold[0].pointCount = 0;
      },
      
      Evaluate: function() {
         var tMani = this.m_manifold[0];
         // replace memcpy
         // memcpy(&this.m0, &this.m_manifold, sizeof(b2Manifold));
         //this.m0.points = new Array(tMani.pointCount);
         var tPoints = this.m0.points;

         for (var k = 0; k < tMani.pointCount; k++){
            var tPoint = tPoints[k];
            var tPoint0 = tMani.points[k];
            //tPoint.separation = tPoint0.separation;
            tPoint.normalImpulse = tPoint0.normalImpulse;
            tPoint.tangentImpulse = tPoint0.tangentImpulse;
            //tPoint.position.SetV( tPoint0.position );

            tPoint.id = tPoint0.id.Copy();

            /*this.m0.points[k].id.features = new Features();
            this.m0.points[k].id.features.referenceFace = this.m_manifold[0].points[k].id.features.referenceFace;
            this.m0.points[k].id.features.incidentEdge = this.m_manifold[0].points[k].id.features.incidentEdge;
            this.m0.points[k].id.features.incidentVertex = this.m_manifold[0].points[k].id.features.incidentVertex;
            this.m0.points[k].id.features.flip = this.m_manifold[0].points[k].id.features.flip;*/
         }
         //this.m0.normal.SetV( tMani.normal );
         this.m0.pointCount = tMani.pointCount;

         b2Collision.b2CollidePoly(tMani, this.m_shape1, this.m_shape2, false);

         // Match contact ids to facilitate warm starting.
         if (tMani.pointCount > 0)
         {
            var match = [false, false];

            // Match old contact ids to new contact ids and copy the
            // stored impulses to warm start the solver.
            for (var i = 0; i < tMani.pointCount; ++i)
            {
               var cp = tMani.points[ i ];

               cp.normalImpulse = 0.0;
               cp.tangentImpulse = 0.0;
               var idKey = cp.id.key;

               for (var j = 0; j < this.m0.pointCount; ++j)
               {

                  if (match[j] == true)
                     continue;

                  var cp0 = this.m0.points[j];
                  var id0 = cp0.id;

                  if (id0.key == idKey)
                  {
                     match[j] = true;
                     cp.normalImpulse = cp0.normalImpulse;
                     cp.tangentImpulse = cp0.tangentImpulse;
                     break;
                  }
               }
            }

            this.m_manifoldCount = 1;
         }
         else
         {
            this.m_manifoldCount = 0;
         }
      },

      GetManifolds: function() {
         return this.m_manifold;
      }
      
   }, {
      
      Create: function(shape1, shape2, allocator) {
         //void* mem = allocator->Allocate(sizeof(b2PolyContact));
         return new b2PolyContact(shape1, shape2);
      },
      
      Destroy: function(contact, allocator) {
         //((b2PolyContact*)contact)->~b2PolyContact();
         //allocator->Free(contact, sizeof(b2PolyContact));
      }
      
   });

   return b2PolyContact;

});
